1. Field of the Invention
The present invention is in the field of chalk bags worn by climbers, and which are used by climbers to carry and dispense chalk onto the climber's hands to improve their grip on climbing surfaces. These chalk bags are used by climbers, such as rock climbers, to carry and dispense chalk onto the climbers hands and fingers both prior to and during climbing.
2. Related Technology
Conventional climber's chalk bags are required to retain chunk or powdered chalk, for example, within the bag while also allowing the climber to quickly and easily access the chalk with either hand during a climb. On the other hand, the conventional chalk bags are so designed that it can be difficult for a climber to access the chalk with the hand. That is, the opening of some conventional chalk bags is a type with a draw-string mouth, and is partially obstructed even when the bag is open. This type of chalk bag closure makes access to the chalk with a climber's hand undesirably difficult. Also, this type of closure can not generally be operated with only a single hand to either open or close the chalk bag.
A conventional closure or fastening device for a pouch (such as a tobacco pouch) is known in accord with British patent No. 26,598, dating from an application filed on 15 Nov. 1897. According to the disclosure of this patent, a tobacco pouch may include a closure having an elongate shape-retaining curved piece of sheet metal which is hinged at its ends to and carries respective ends of a matching elongate flexible and resilient piece of metal. The pouch is secured at its mouth to the closure by folding the flexible cloth or leather material, for example, of the pouch over the closure to form a sewn hem. The flexible piece of metal may be manually sprung between a position in which it lays adjacent to the curved piece, closing the pouch; and another position sprung away from the curved piece of metal. In the second position of the flexible piece of metal as described, the pouch will have a somewhat ellipsoidal-shaped opening.
Similar closures are disclosed in U.S. Pat. No. 2,040,271, issued 12 May 1936 to D. Rosenzweig; and U.S. Pat. No. 2,150,627, issued 14 Mar. 1939 to I. Lieber. Each of these closures include an elongate curved substantially rigid member hingeably connected near its ends to respective ends of an elongate flexible and resilient member. The flexible member may be manually snapped between an open and a closed position. In the closed position of the flexible member, the pouch, handbag or container, for example, which is fitted with the closure device will be closed and will have a curved configuration. In the open position of the closure, the mouth of the pouch or handbag will be open to a generally elliptical shape.
All of these conventional closures when open provide an opening which is an ellipsoid, or is shaped like a pair cycloidal segments or circular segments arranged on opposite sides of an axis of symmetry. These opening shapes provide a pair of opposite cusps or corners from which contents may be poured. However, for a climber's chalk bag, the contents of the bag are not intended to be poured out. In fact, an opening shape with a defined cusp or corner is undesirable because climbers may maneuver their bodies while climbing into positions in which the chalk is poured out of such a chalk bag and is lost. Also, the existence of such cusps is undesirable for a climber's chalk bag because the access to the contents of the bag is made more difficult by the opening shape which does not best accommodate the human hand.
An additional conventional bi-stable closure device for flexible bags is known in accord with U.S. Pat. No. 3,782,601, issued 1 Jan. 1974 to A. A. Krawagna. According to the disclosure of this patent, a snap-closure includes a plate portion and a collar portion integral along one edge with the plate portion via a flexible web. The plate and collar seek one of two stable positions. In one of these stable positions, a corner opening of a bag to which the closure is secured is open so that contents of the bag can be dispensed though the opening. In the other of the two stable positions, the walls of the bag are strung tightly across the plate portion of the closure to close the bag opening.
However, none of these conventional closure devices provides a substantially circular and unobstructed opening when open and also closes tightly when closed. Desirably, a climber's chalk bag should provide a circular opening just sufficiently large enough to accept a climber's hand for chalking, but also sufficiently small as to retain the chalk contained in the bag. That is, the opening should not be larger than required for inserting the climber's hand, and should not have a shape which facilitates spilling or loss of the chalk from the open bag. Further, such a climber's chalk bag should be easily opened and closed with a single hand, and with either hand. Additionally, such a climber's chalk bag should provide a shape-retaining opening which when open allows a climber to easily and certainly insert the fingers or an entire hand for chalking, and without an overly tight opening which could trap or catch the climber's hand at a critical moment.